GB2169917A

GB2169917A - Built detergent composition containing stabilised polyethylene terephthalate-polyoxyethylene terephthalate soil release promoting polymer

Info

Publication number: GB2169917A
Application number: GB08601534A
Authority: GB
Inventors: Loretta Kathleen Ciallella
Original assignee: Colgate Palmolive Co
Current assignee: Colgate Palmolive Co
Priority date: 1985-01-23
Filing date: 1986-01-22
Publication date: 1986-07-23
Also published as: FI80069B; ATA13486A; KR940000437B1; CA1248427A; PT81884A; AU587006B2; SE461657B; JPH075908B2; SE8600248L; SE8600248D0; PT81884B; BE904080A; AU5248186A; BR8600258A; IT8647563A0; DK163364C; FR2576316B1; FI860313A; DE3601481A1; FR2576316A1

Description

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GB 2 169 917 A

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SPECIFICATION

Built nonionic detergent composition containing stabilised polyethylene terephthalate-polyox-5 yethylene terephthalate soil release promoting polymer

The present invention relates to built detergent compositions containing polyethylene terephthalate 10 (PET)—polyoxyethylene terephthalate (POET) soil release promoting polymers. More particularly, it relates to built nonionic detergent compositions containing such stabilised PET-POET polymer, the stabilisation of which is effected by fusing the 15 PET-POET polymer, at elevated temperature, with a polyacryfate, so that the PET-POET polymerandthe polyacrylateform a homogenous melt, and converting such meltto particulate form, in which the PET-POET polymerandthe polyacrylate remain in 20 intimate contact. The stabilised PET-POET polymers so made are superior in stability, as shown by superior soil release promoting properties, when stored, even at elevated temperatures, in contact with alkaline materials, such as alkaline builders for detergent 25 compositions, when such polymers are incorporated in such compositions. It has been found that such stability is also superior to that of PER-POET polymers coated with polyacrylate or intimately mixed with polyacrylate in finely divided forms. When the stabil-30 ised particulate soil release promoting polymers are incorporated in nonionic detergent-based detergent compositions, soil and stain removing properties of such compositions are improved, compared to compositions ofsimilarformulas wherein the PET-POET 35 polymerandthe polyacrylate are present as mixed individual powders.

PET-POET polymers have been described in the patent literature as useful to promote soil release from laundry that had previously been treated with such a 40 polymer by washing with a detergent composition containing it. US patent 3,962,152 and British patent 1,088,984 both teach soil releasing effects. It has been found that such polymeric materials can be destabilised by anionic detergents and/or alkaline com-45 pounds. Therefore, when detergent compositions are made containing PET-POET polymers such polymers tendtolosetheirsoil release promoting properties on storage if the detergent compositions contain alkaline builder salts, such as sodium carbonate or other 50 alkaline materials, with the most significant losses in such activity being in those compositions which are more strongly alkaline and which are stored at more elevated temperatures for longer periods of time. Accordingly, efforts have been madeto stabilise the 55 soil release promoting polymers, so that their desirable properties will not be lost when they are incorporated in built detergent compositions.

The applicants have discovered that when a PET-POET polymer is melted and mixed with a water 60 soluble polyacrylate, such as sodium polyacrylate, preferably of a molecular weight in the range of about 1000 to 5000, e.g. about 2000, in a proportion within the range of about2:1 to8:1 (PET-POET polymerto polyacrylate) and the melt is converted to particulate solid form, with the mentioned polymers still being in intimate contact in such form, the soil release properties of the PET-POET polymer are retained despite storage of the described particles in contact with particulate alkaline materials, such as builder salts for synthetic organic detergents, which are often present in built particulate detergent compositions. This discovery was surprising, especially because various other polymeric materials are unsatisfactory for stabilisation of the PET-POET polymers. Also, coating of powdered PET-POET polymer with a solution of sodium polyacrylate, followed by drying such coating, does not result in the same desirable stabilisation, nor does mixing together of finely divided powders of such polymers. To obtain the applicant's results initial fusion together of the polymers is required. Such requirement is surprising because it would have been expected that there would be an interaction between the polymers at elevated temperature orthat the elevated temperature would have contributed to the destabilisation of the soil release promoting polymer. A further desirable effect noted is the improvement in cleaning of soiled and stained materials of various types during washing with built nonionic detergent compositions containing the particulate stabilised soil release promoting polymer of the present invention. Such washing yields noticeably cleanerfabrics, compared to cleaning with detergent compositions containing PET-POET polymers and sodium polyacrylate in powdered form. This result is also surprising because the cleaning effects are not related to soil release promotion, and the soiled fabrics were not previously treated with the soil release promoting agent.

The molecular weight of the PET-POET polymer will usually be in the range of about 15,000 to 50,000, preferably being about 19,000 to 43,000, more preferably being about 19,000 to 25,000, e.g. about 22,000. Such molecularweightsare weight average molecular weights, as distinguished from number average molecular weights, which, in the case of the present polymers, are often lower. In the polymers utilised in the present invention the polyoxyethylene will be of a molecular weight in the range of about 1,000 to 10,000, preferably about 2,500 to 5,000, more preferably 3,000 to 4,000, e.g. about3,400. In such polymers the molar ratio of polyethylene terephthalate to polyoxyethyleneterephthalate units (considering

O 0

[ OCH2CH2O-C- vOy ~C ] as a PET unit and

O O

C (OCH2CH2)n-Q-C— ~C ] as a POET unit)

will be within range of 2:1 to 6:1, highly preferably 5:2 to 5:1, even more preferably 3:1 to 4:1, e.g. about 3:1. The proportion of ethylene oxide to phthalic moiety in the polymer will be at least 10:1 and often will be 20:1

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105

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Formulae in the printed specification were reproduced from drawings submitted after the date of filing, in accordance with Rule 20(14) of the Patents Rules 1982.

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or more, preferably being within the range of 20:1 to 30:1 and more preferably being about 22:1. Thus, it may be seen thatthe polymer may be considered as being essentially a modified ethylene oxide polymer 5 with the phthalic moiety only a minor component thereof, whether calculated on a molarorweight basis, it is considered surprising that with such a small proportion ofethyleneterephthalateor polyethyleneterephthalateinthepolymerthepolym-10 er is sufficiently similarto the polymer of the polyesterfibre substrate (or other polymers to which it is adherent, such a polyamides) as to be retained thereon during washing, rinsing and drying operations.

15 Although the described PET-POET polymer is that which is employed normally be the applicants in accordance with the present invention, and which is highly preferred for its desired functions, other PET-POET polymers, such as those described in the 20 previously mentioned US and British patents, may also be employed and could be improved (stabilised) in accordance with the present invention. However, the soil release promoting properties of such materials may not be as good as those of the preferred 25 polymers.

The polyacrylate employed is a low molecular weight polyacrylate, the molecular weight of which is usually within the range of about 1,000 to 5,000, preferably being in the range of 1,000 to 3,000 and 30 most preferably being between 1,000 and 2,000, e.g. about2,000.The mean molecularweightwill usually be within the range of 1,200 to 2,500, such as 1,300 to 1,700. Although otherwatersolublepolyacrylates may sometimes be substituted in partforthe 35 described sodium polyacrylate, including some other alkali metal polyacrylates, e.g. potassium polyacrylate, it is preferred that such substitutions, when permitted, be limited to a minor proportion of the material, and preferably, the polyacrylate employed 40 will be an unsubstituted sodium polyacrylate. Such materials are available from Alco Chemical Corporation, underthe name Alcosperse. The sodium polyacrylates are available as clear amber liquids or powders, completely soluble in water, with the 45 solutions being of about 25 to 40% solids contents, e.g. 30%, and with the pH of such solution or of a 30% aqueous solution of a powder being in the range of 7.5 to 9.5. Among these products those preferred are presently sold as Alcosperse 104,107,107D, 109 and 50 149, of which Alcosperse 107D, a 100% solids powder, is highly preferred, although Alcosperse 107, a 30% aqueous solution, may be used instead with little difference in results (provided that it is dried first). Both are sodium polyacrylates with the liquid 55 (107) being of a pH in the 8.5 to 9.5 range and the pH of the powder (107D) being inthe7.0to 8.0 range, at 30% concentration in water. The powder is preferably anhydrous, but may contain a minor proportion of water, normally lessthan 10%, which is largely 60 removed during thefusion operation.

To practise the process of the present invention and to make the stabilised soil release promoting po!ymerthereof,fo!lowing normal procedure,the PET-POET polymer is melted by being raised to a 65 temperature above its melting point and preferably to a temperature in the range of 70 to 150°C, to liquefy it, and powdered solid sodium polyacrylate is added to the melt, as described. When a uniform melt has been obtained it may be cooled and the solidified mass 70 may be size reduced by any suitable means. Preferably, cryogenic grinding orflaking operations will be employed so that the product will be a finely divided powder orflake which will be readily miscible with other components of a built detergent composition, 75 and will not segregate objectionably from such composition. Cryogenic size reduction, often undertaken at a temperature below 0°C, and sometimes below—50°C, may be effected by grinding or otherwise size reducing in the presence of liquid 80 nitrogen or other cryogenic material. Alternatively, a suitable grinder, such as a hammer mill, a cage mill or a Raymond Imp Mill may be employed, and instead of liquid nitrogen or other liquid cryogenic coolant, solidified carbon dioxide (dry ice) may be mixed with 85 the resins being ground, or other cooling facilities maybe utilised to prevent overheating ofthe material and to maintain it in cold, readily fracturable form. Instead ofthe mentioned size reduction devices others of equivalentfunction may be utilised, includ-90 ing the Raymond Ring-Roll Mill, which contains an internal separatorand is capable of producing very finely divided resinous materials.

Instead of utilising cryogenic or lowtemperatures grinding equipmentto size reduce the solidified melt 95 of PET-POET and polyacrylate, the melt may be spray cooled to desirably sized beads, which will usually pass through a No. 10 sieve (US Sieve series) (which has openings 2000 microns across) and preferably will pass through a No. 30 sieve (which has openings 100 590 microns across).

The product resulting from the application ofthe process ofthe present invention may be considered as PET-POET polymer carrying polyacrylate. Because the proportion ofthe polyacrylate is relatively minor 105 (although its effect is significant) the PET-POET polymer provides a medium for distributing the polyacrylate throughout any detergent composition with which it is mixed. Thus, in addition to the stabilising effect the polyacrylate has on the PET-110 POET polymer, the polymer helps to extend the polyacrylate so that it may be more uniformly distributed throughoutthe detergent composition and thereby more uniformly impartto such composition desirable properties ofthe polyacrylate, which 115 include promotion of clay soil removalfrom laundry during washing and inhibition of soil redeposition on the laundry during washing. The "carrying" ofthe polyacrylate by the stabilised polymer also obviates the need to spray the detergent composition beads or 120 base beads with a solution of polyacrylate to distribute it evenly throughout the detergent composition.

The primary intended use forthe stabilised PET-POET polymers isfor soil release promotion in detergent compositions. It has been found that 125 laundry in which the fabrics are of polyesters or polyester blends (usually with cotton), more readily release various soils to the wash water during washing with built synthetic organic detergent compositions, especially those based on nonionic deter-T30 gents, if the soiling ofthe laundry takes place after it

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has been washed with such a detergent composition containing the PET-POET polymer. Some ofthe polymer is held to the laundry during the washing operation, so that it is presentthereon when the 5 laundry is subsequently soiled, and its presence promotes the removal ofthe soil and/or stain during a subsequent washing. It could have been expected that the polyacrylate, in the same particles as the PET-POET polymer would promote dispersion ofthe 10 polymer and inhibit deposition thereof on the laundry but such is not the case. Instead, the polyacrylate increases the soil release promting activity ofthe PET-POET polymer in detergent compositions by inhibiting decomposition or degradation ofthe po-15 lymer when it is subjected to contact with alkaline materials, as in such built detergent compositions in which the builder salt is alkaline (as many of them are).

The detergent compositions to which the stabilised 20 PET-POET polymers ofthe present invention may be added or in which such may be included, to give the detergent composition desirablesoil release promoting properties, are built synthetic organic detergent compositions. The synthetic organic detergent will 25 normally be a nonionic detergent, although in some instances anionic detergent may be useful. Anionic detergents usually tend to inactivate the PET-POET polymer but, if they are employed in small proportions in basically nonionic detergent compositions, 30 the use ofthe present stabilised PET-POET polymer results in compositions having better soil release promoting activities than result whenthe PET-POET polymer is used without the stabilising polyacrylate having previously been fused with it.

35 Ofthe nonionic detergents it is preferred to employ those which are condensation products of ethylene oxide and/or propylene oxide with each other and with hydroxyl-containing bases, such as higherfatty alcohols, Oxo-type alcohols and nonyl phenol. Most 40 preferably, a higherfatty alcohol is employed and is of 10to20carbon atoms, preferably 12to15or16 carbon atoms, and the nonionic detergent contains from about3to 20 or 30 ethylene oxide groups per mole, preferably 6 to 11 or 12. Most preferably the 45 nonionic detergent will beone in which the higher fatty alcohol is of about 12 to 15 or 12 to 14 carbon atomsand which contains from6or7to 11 moles of ethylene oxide. Among such detergents is Alfonic (RegisteredTrade Mark) 1214-60C, sold by Conoco 50 Division of E. I. DuPont De Nemours, Inc., and Neodols (Registered Trade Mark) 23-6.5and 25.7, availablefrom Shell Chemical Co. Among their especially attractive properties, in addition to good detergency with respectto oily and greasy soil 55 deposits on goods to be washed, and excellent compatibility with the present polymeric release agents, is a comparatively low melting point, which is still appreciably above room temperature, so that they may be sprayed onto base beads as a liquid 60 which solidifies quickly after it has penetrated into the beads.

Various builders and combinations thereof which are effective to complement the washing action ofthe nonionic synthetic detergent(s) and to improve such 65 action include both water soluble and water insoluble builders. Of thewatersoluble builders, which preferably are employed as mixtures, both inorganic and organic builders may be used. Among the inorganic builders those of preference include: various phos-70 phates, usually polyacrylates, such asthetripoly-phosphatesand pyrophosphates, more specifically the sodium tripolyphosphates and sodium pyrophosphates, e.g. pentasodiumtripolyphosphate,tetraso-dium pyrophosphates; sodium carbonate; and 75 sodium silicate; and mixtures thereof. Instead of a mixture of sodium carbonate and sodium bicarbonate, sodium sesquicarbonate may often be substituted. The sodium silicate, when employed, is normally of Na20: Si02 ratio within the range of 1:1.6 80 to 1:3, preferably 1:2.0to 1:2.4or 1:2.8, e.g. about 1:2.4.

Ofthe water soluble inorganic builder salts the phosphates will usually be employed with a lesser proportion of sodium silicate, the carbonates will be 85 employed with bicarbonate, and sometimes with a lesser proportion of sodium silicate, and the silicate will rarely be used alone. Instead of individual polyphosphates being utilised it will sometimes be preferred to employ mixtures of sodium pyrophos-90 phate and sodium tripolyphosphate in proportions within the range of 1:10 to 10:1, preferably 1:5 to 5:1. Of course, it is recognised that changes in phosphate chemical structure may occurduring crutching and spray so thatthefinal product may differ somewhat 95 from the components charged to the crutcher.

Ofthe water soluble organic builders, nitrilotriace-tic acid salts, e.g. trisodium nitrilotriacetate (NTA), preferably employed as the monohydrate, are preferred. Other nitrilotriacetates, such as disodium nitri-100 loacetate, are also useful. The various water soluble builder salts may be utilised in hydrolated forms, which are often preferred. Other water soluble builders that are considered to be effective include the inorganic and organic phosphates, borates, e.g. 105 borax, citrates, gluconates, ethylene diamine tetraacetates and iminodiacetates. Preferably the various builders will be in theforms of their alkali metal salts, either the sodium or potassium salts, or mixtures thereof, but sodium salts are normally more 110 preferred. In some instances, as when neutral or slightly acidic detergent compositions are being produced, acid forms ofthe builders, especially ofthe organic builders, may be preferable but normally the salts will either be neutral or basic in nature, and 115 usually a 1% aqueous solution ofthe detergent composition will be of a pH inthe rangeof9to 11.5, e.g.9to 10.5.

Insoluble builders, generally ofthe Zeolite Atype, may be used advantageously in the compositions of 120 the present invention, and of these, hydrated Zeolites X and Y may be useful too, as may be naturally occurring zeolites and zeolite-like materials and other ion-exchanging insoluble compounds that can act as detergent builders, ofthe various Zeolite A products, 125 Zeolite 4A has been found to be preferred. Such materials are well known intheartand method for their manufacture need not be described here. Usually such compounds will beoftheformula (NA20)x (AI203)y-(Si02)z-w H20 130 wherein x is 1, y is from 0.8 to 1.2, preferably about 1, z

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is from 1.5 to 3.5, preferably 2 to 3 or about 2, and w is from 0 to 9, preferably 2.5 to 6.

Thezeolitebuildershould be a univalent cation-exchanging zeolite, i.e. it should be an aluminosili-5 cate of a univalent cation such as sodium, potassium, lithium (when practicable) or other alkali metal or ammonium. Preferably the univalent cation ofthe zeolite molecularsieve is an alkali metal cation, especially sodium or potassium, and most preferably 10 it is sodium. The zeolites, whether crystalline or amorphous, are capable of reacting sufficiently rapidly with calcium ions in hard water so that, alone orin conjunction with other watersoftening compounds in the detergent composition, they soften the 15 wash water before adverse reactions of such ions with other components ofthe synthetic organic detergent composition occur. The zeolites employed may be characterised as having a high exchange capacityforcalcium ion, which is normally from 20 about 200 to 400 or more milligram equivalents of calcium carbonate hardness per gram ofthe alumino-silicate, preferably 250 to 350 mg eq/g on an anhydrous zeolite basis. Also, they preferably reduce the hardness quickly in wash water, usually within the 25 first30secondsto five minutes afterbeing added to the wash water, and lowerthehardnesstolessthana milligram of CaC03 per litre within such time. The hydrated zeolites will normally be of a moisture content in the range of 5 to 30%, preferably about 15 30 to 25% and more preferably 17 to 22%, e.g. 20%.The zeolites, as charged to a crutcher mixfrom which base beads may be made, should be in finely divided state, with the ultimate particle diameters being up to 20 microns, e.g. 0.005 to 20 microns, preferably 0.01 35 to 8 microns mean particle size, e.g. 3 to 7 microns, if crystalline, and 0.02 to 0.1 micron, e.g. 0.01 to 0.05 micron, if amorphous. Although the ultimate particle sizes are much lower, usually the zeolite particles will be of sizes within the range of No. 100 to 400 sieve 40 (U.S. Sieve Series) (which have openings 149 to 37 microns across), preferably No. 140 to 325 sieve (which have openings 105 to 44 microns across), as charged to the crutcherforthe manufacture ofthe base beads. In the base beads the zeolite(s) will often 45 desirably be accompanied by a suitable builder salt or salts, e.g. sodium tripolyphosphate, sodium carbonate, sodium bicarbonate. Sodium silicate may tend to agglomerate with zeolites so the proportion thereof present in zeolite-built base beads may be limited, as 50 to 2 or3%, or it may be omitted, especially for carbonate-containing formulations, but sometimes as much as 5 to 10% may be present, as in NTA-built products.

When employing the preferred nonionic deter-55 gents in detergent compositions to which the powder orflakes ofthe present invention are added to impart soil release promoting properties, either polyphosphate or carbonate builders are normally employed. However, the carbonates, being of higher alkalinity, 60 have a more detrimental effect on the stability ofthe PET-POET polymer and accordingly, detergent compositions built with carbonates, and which contain unstabilised PET-POET polymer, can often lose the soil release promoting activity ofthe polymer after 65 relativelyshortstorage periods. Accordingly,the need forthe present invention is greatest for detergent compositions built with carbonates.

In addition to the synthetic organic detergent and builder, detergent compositions will usually also 70 contain a limited proportion of moisture and various adjuvants. Among the adjuvants are fabric softening materials, such as bentonite and other clay fabric softeners, fluorescent brighteners, such as the distil-bene brighteners, enzymes, such as proteolytic and 75 amylolytic enzymes, colourants, such as dyes and pigments, and perfumes. In preferred detergents the nonionic detergent (preferably Neodol 23-6.5), is post-sprayed onto base beads (largely builder) and constitutes from 10 to 30%, more preferably 15 to 80 25% and most preferably about 20% ofthefinal composition. In the final composition the moisture content will usually be from 4to 14%, preferably5to 10%,e.g.about7 or8%, preferably 2 to 4%, e.g. about3%, the enzyme content will normally be from 85 0.5to3%,preferably 1 to2%,e.g.about1.5%,the polyacrylate content willl be from 0.3 to 3%, preferably 0.5 to 2%, e.g. 1 % or about 1 % and the PET-POET polymer content willl be from 2 to 10%, preferably 2 to 6%, and more preferably about 4%. Such composi-90 tions may also often have present a relatively small proportion usuallyfrom 0.5 to 3%, of magnesium sulphate, which is added to the crutcherto prevent undesirable setting ofthe crutcher mix forthe base beads. To manufacture the detergent compositions 95 described a crutcher mix is made at a temperature of about 50 to 70°C and a moistu re content of about 30 to 60%, ofthe clays, builders, magnesium sulphate, colourants andfluorescent brightener, and such is spray dried, in the normal manner, using a conven-100 tional production spray tower in which hot combustion products, e.g. rushing upthetower, dry atomised droplets ofthe crutcher mixfalling down the towerto produce the base beads, which normally will be of particle sizes in the range of 10 to 100, U.S. Sieve 105 series (which have openings 2000 to 149 microns across). Onto such dried particles there will be sprayed or dripped molten nonionic detergents, which will be absorbed by the beads and will solidify in them. After which there will be mixed with the 110 resulting builtdetergent composition the powdered orflaked stabilised PET-POET polymer, of particle sizes less than No. 30, U.S. Sieve Series (which has openings 590 microns across), (preferably 30-100 (which have openings 590 to 149 microns across)). 115 Enzyme powder, if present, will then be mixed in. Alternatively, in some processes the stabilised polymer may be mixed with the enzyme powder before blending with the rest ofthe particulate detergent. In some procedures the stabilised polymer may be 120 blended with the base beads before application ofthe nonionic detergent, and the nonionic detergent may then serve to hold the polymer particles more strongly to the base beads. The various blending operations may be conducted in conventional in-125 clined drum ortwin-shell blenders or in other suitable equipment. Perfume, when present, may be applied at any suitable stage, but usually is the last component added.

The invention may be put into practice in various 130 ways and a number of specific embodiments will be

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described to illustrate the invention with reference to the accompanying examples. Unless otherwise indicated, all partsand percentagesarebyweightandall temperatures are in °C in the examples, specification 5 and claims.

EXAMPLES 1A, IB AND 1C A detergent composition is made up having the composition set out in Table 1 below.

TABLE 1

10 Component Percent

Zeolite 4A, hydrate (20% moisture content,

powder) 26.0

Sodium carbonate, anhydrous 18.3

Sodium bicarbonate 15.7 15 BentoliteL(fabricsofteningclay) 3.0 Fluorescent brightener (stilbene type) 1.7 Proteolytic enzyme (Maxatase MP) 1.5 Magnesium sulphate 1.0 Blue dye 0.1

20 Neodol 23-6.5 (nonionic detergent) 20.0 Alkaril QCF (PET-POET soil release promoting agent) 4.0

Alcosperse 107D (stabiliser) 1.0

Perfume 0.2

25 Moisture 7.5

100.0

In the making of a detergent composition ofthe formula of Table 1, first, an aqueous crutcher mix 30 containing about 50% water and the formula proportions of zeolite, carbonate, bicarbonate, Bentolite L, fluorsecent brightener, magnesium sulphate and dye is made at a temperature of about 60°C. This is spray dried in a conventional production spray drying 35 tower ofthe type employed for spray drying various commercial detergent compositions. The base beads produced, of particle sizes in the Nos. 10 to 100 range, U.S. Sieve Series (which have openings 2000 to 149 microns across) are then sprayed with liquid state 40 (molten) nonionic detergent, which is at a temperature of about 55 to 60°C, in a suitable mixer, such as a rotating inclined drum or a twin-shell blender. The enzyme powder is then blended with the detergent composition, followed by the stabilised PET-POET 45 polymer (containing sodium polyacrylate). The stabilised polymer had previously been made by melting theformula proportion of Alkaril QCF (desirably anhydrous but it may contain a small proportion of moisture) at a temperature ofabout82°Cand mixing 50 into ittheformula proportion of Alcosperse 107D (sodium polyacrylate). After such components are thoroughly mixed together so as to form a uniform meltthe melt is cooled to solidify it and the resulting mass is cryogenically ground, using any ofthe 55 grinders previously mentioned, but preferably a hammer or cage mill, so as to be of particle sizes that pass through a No. 30 sieve, U.S. Sieve Series (which has openings 590 microns across), preferably being of sizes in the range of 30to 100, U.S. Sieve Series 60 (which have openings 590 to 149 microns across). Afterthe stabilised PET-POET polymer, with the stabilising polyacrylate present in the particles thereof, is blended with the detergent composition particles the formula proportion of perfume is sprayed 65 ontotheblend,whileitiskeptin motion, as by mixing in an apparatus such as one of those previously mentioned. The resulting product is a satisfactory built nonionic synthetic organic detergent composition of good detergency and of useful soil release 70 promoting characteristics. The soil release promoting polymertherein is stabilised so that after prolonged storage or after storage at elevated temperature for two weeks, the composition exerts appreciably more soil release promoting action than a 75 control composition ofthesameformula inwhichthe Alkaril QCF is present in the base beads or is applied alone to the detergent composition particles (without polyacrylate being present).

Surprisingly, the soil release promoting action, 80 after ageing, ofthe detergent composition of this example is superior to that of a composition of the sameformula (4:1 PET-POET:polyacrylate) wherein the QCF and Alcosperse powders are mixed together and then applied to the detergent composition beads, 85 and the composition is also superior in soil release promotion to a composition ofthe formula of this example, wherein the QCF powder is applied to the detergent composition beads and theformula proportion of Alcosperse 107D, in aqueous solution (or as 90 Alcosperse 107) is then sprayed onto the detergent composition particles.

To test the soil release promoting action ofthe product ofthe present invention, compared to a control, wherein the same proportion of PET-POET 95 polymer is present in the detergent composition, detergent compositions ofthe formula of Table 1 previously given were made, to one of which the stabilised soil release promoting polymerwas added (Example 1A) and to the other of which (Example 1B) 100 the same proportion of such polymerwas added, without previously undergoing the stabilising treatment recited herein. Subsequently, both products were stored for two weeks at 43°C, which approximates to the elevated temperatures reached in some 105 warehouses. After such storage both the "experimental" (Example 1 A) and "control" (Example 1B) compositions are used to wash clean polyester doubleknit swatches in wash water containing 150 ppm hardness, as calcium carbonate (3:2 calcium-110 :magnesium hardness salt ratio) at a temperature of 49°Cin an automatic washing machine, so as to depositthesoil release promoting polymeronthem, with the detergent composition concentration being 0.06% of the wash water, and then the swatches are 115 soiled and washed at the same concentration and in thesametype of wash water with the same detergent composition. The percentage of soil removal was then calculated and it wasfound that the experimental formula (Example 1 A) lost 1.2% of its 120 initial soil removing power (before ageing), whereas the composition containing "regular" PET-POET polymer (Example 1B) Lost 84.5% of its initial soil removing power. Before ageing the soil removing powers of both the "experimental" and the "control" 125 composition were essentially the same.

When, instead ofthe polyacrylate being fused with the soil release promoting polymer,followed by cooling ofthe mass and size reduction thereof, the PET-POET polymer and polyacrylate powders are 130 mixed and blended with the detergent composition.

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to produce a product ofthe same formula as given in this example, after accelerated ageing tests it isfound thatthesoil release promoting polymerstill deteriorates objectionably and similar results are obtainable 5 when the unstable polymer is mixed with the detergent composition in the proportion given, and theformula proportion of polyacrylate, in aqueous solution, is sprayed onto the polymer and other detergent composition components. 10 In a cleaning test, known as a multi-stain test, in which cleaning powers of detergent compositions are measured, various stains, including grape juice, blueberry pie, brewed tea, cranberry juice, beef liver blood, chocolate fudge pudding, potting soil, Brandy 15 black clay, liquid make-up, sebum/particulatesoil, Bic black pen ink, barbecue sauce, red Crisco shortening and French dressing are deposited on a variety of fabrics, including Dacron (Registered Trade Mark) cotton blend, Qiana (Registered Trade Mark) nylon, 20 cotton and doubleknit Dacron, fabrics likely to be present in a family wash, and the stained and soiled fabrics are washed in test washing machines, with reflectances (indicative of cleaning power) ofthe various swatches being measured afterwashing and 25 drying thereof. Using the unaged product ofthe present invention (Example 1 A) as described in this example, compared to a control product (Example 1C) not containing the PET-POET polymerandthe polyacrylate, but otherwise the same as that ofthe 30 formula of this example, it is found that the total of Rd values forthe 22 different swatch combinations employed was significantly higherforthe experimental than forthe control product, indicating improved cleaning power. Note that this is notan 35 indication of soil release promotion because the swatches were not washed with the detergent composition to deposit PET-POET polymertherein before staining.

EXAMPLES 2A, 2B AND 2C 40 A detergent composition including stabilised PET-POET polymer is made by the method described for Example 1Awith the exception thatthefusion ofthe PET-POET polymer and polyacrylate takes place at a temperature in the range of 130°C to 150°C. The 45 product made (Example 2A) is ofthe same formula as in Example 1 A, but the particles ofthe stabilised polymer are of particle sizes that pass through a No. 16 sieve (U.S. Sieve Series) (which has openings 1190 microns across) instead of a No. 30 sieve. This 50 productistestedinthesamemannerasdescribed in Example 1 for soil release promoting agent stability and found that only 9.6% deterioration occurs after two weeks accelerated ageing.

In a variation of this (Example 2B) the stabilised 55 polymer (with polyacrylate presenttherein) is applied to the base beads before spraying on ofthe nonionic detergent. The product of such process shows a loss of soil release promoting activity {or a deterioration of the PET-POET polymer) of 9.1 %. When the PET-POET 60 polymerandthesodium polyacrylate are applied to the base beads orthe detergent composition beads as a mixed powder (not previously fused, cooled and ground) (Example 2C) the loss in soil release promoting activity is much higher, being about 30%. 65 EXAMPLE 3

A detergent composition is made up having the composition as set out in Table 2 below.

Table 2

Component Percent

Pentasodiumtripolyphosphate 59.4 Neodol 25-7 (or Neodol 23-6.5) (nonionic detergent) 20.0

Moisture 9.5

Alkaril QCF (PET-POET polymer) 4.0

Sodium polyacrylate (Alcosperse 107D) 1.0

Sodium silicate (Na20:Si02=1:2.4) 3.0

Enzyme (Maxatase MP) 1.5

Fluorescent brightener (Tinopal 5BM) 1.3

Perfume 0.2

Blue dye 0.1

100.0

A detergent composition ofthe above formula is made in essentially the same manner as thatde-scribed forthe composition of Example 1 A, butwith the sodium tripolyphosphate, fluorescent brightener and dye being crutched and spray dried to base bead form, the nonionic detergent being sprayed onto the resulting beads (of particle sizes in the Nos. 10 to 100 range, U.S. Sieve Series), the enzyme powder and stabilised PET-POET polymer (containing sodium polyacrylate) (made as described in Example 1) being subsequently mixed with the detergent composition beads, and such mixture then being perfumed.

The resulting product is a satisfactory built nonionic synthetic organic detergent composition of good detergency and of useful soil release promoting characteristics. The soil release promoting polymer in the composition is stabilised so that after prolonged storage at room temperature or after storage at elevated temperature fortwo weeks, the composition exerts more soil release promoting action than does a control composition ofthe sameformula in which the Alkaril QCF is present in the base beads or is applied alone to the detergent composition particles (in both cases without any polyacrylate being present). As was mentioned with respectto the composition of Example 1, the soil release promoting action ofthe detergent composition ofthe present example, after ageing issuperiorto that of a similarly aged composition ofthe sameformula (also containing PET-POET and polyacrylate in 4:1 proportion) wherein the QCF and Alcosperse 107D powders are mixed together (withoutfusion) and are then applied to the detergent composition beads, in powderform, and the composition of this example is superior in soil release promotion, after ageing, to compositions of theformula of this example wherein the QCF powder is applied to the detergent composition beads and the formula proportion of Alcosperse 107D,in aqueous solution (or as Alcosperse 107) is then sprayed onto the detergent composition particles.

In summary, when the soil release promoting action and the cleaning powers ofthe composition of the present invention are measured in the manner described in Example 1, and when the described controls are tested in the manner reported in such example, substantially the same types of results are obtainable as reported in example 1 and such results showthe superiority ofthe compositions ofthe

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7 GB 2 169 917 A 7 present invention, in which previously fused Alkaril QCF—Alcosperse 107D is present, compared to a control. Such results are confirmed by repeated launderings of soiled laundry with the compositions 5 ofthe present example. EXAMPLE 4 When the components of the formulas of Examples 1 and 3 are varied, as taught in the specification, and when the proportions are changed ±10%, ±20% and 10 ±30%, while still being kept within the ranges recited, detergent compositions of improved stability, compared to controls not containing the stabilised PET-POET polymer, are obtained. Similarly, when the manufacturing methodsforthe production ofthe 15 stabilised polymer are modified, as previously taught, the products resulting are still of improved stability ofthe PET-POET polymer and are suitable for use in detergent compositions containing alkaline builder materials, which compositions are expected 20 to be stored for long periods of time or which will be subjected to elevated temperatures during storage. Thus, for exam pie, when the proportions of nonionic detergent, builder, PET-POET, polyacrylate and moisture are in the ranges of 10 to 30%, 30 to 25 75%, 2to 10%, 0.3to 3% and4to 14%, respectively, preferably 15 to 25%, 50 to 70%, 2 to 6%, 0.5 to 2%, and 5 to 11%, respectively, superior soil release promoting built detergent compositions will result. When the builder is a mixture of sodium carbonate, 30 sodium bicarbonate and zeolite the proportions of such components will preferably be in the ranges of 10to30%, 10to 25% and 15to40%, respectively, and when the builder is sodium tripolyphosphate or a mixture thereof with sodium pyrophosphate the 35 proportion thereof will usually be in the range of 30 up75%, preferably 50 5070%. The invention has been described with respect to various illustrations and embodiments thereof but is not to be limited to these because it is evident that 40 oneofskill in the art, with the present specification before him, will be able to ultilise substitutes and equivalents without departing from the invention. CLAIMS

1. Asoil release promoting built synthetic organic 45 detergent composition comprising a detersive proportion of detergent, a building proportion of builder forsuch detergent, a soil release promoting polymer and an anti soil redeposition polymer, such soil release promting polymer and anti soil redeposition

50 polymers being in intimate contact in solid particles, and the other components ofthe detergent composition being in particulate form.

2. Asoil release promoting built synthetic organic nonionic detergent composition comprising a deter-

55 sive proportion of nonionic detergent or a mixture of nonionic detergent and a small proportion of anionic detergent, a building proportion of alkaline builder for such detergent or detergents, a soil release promoting proportion of soil release promoting 60 polymer of polyethylene terephthalate (PET) and polyoxyethyleneterephthalate (POET), and a stabilising proportion of watersoluble polyacrylate (PA), which stabilises the PET-POET polymer against deterioration and loss of soil release properties on 65 storage in contact with alkaline materials, such

PET-POET and PA polymers being in intimate contact in solid particles, and the other components ofthe detergent composition being in particulate form, the small proportion of any anionic detergent present 70 being insufficientto destroy the benefits ofthe presence ofthe PET-POET and PA.

3. A particulate composition as claimed in Claim 1 or Claim 2 in which the soil release promoting polymer, with anti soil redeposition polymer in

75 intimate contact therewith, is that resulting from fusing release promoting polymer and anti soil redeposition polymers at elevated temperature and converting the melt to solid particles which contain the soil release promoting polymers and anti soil 80 redeposition polymers.

4. A composition as claimed in any one of Claims 1 to 3 in which the PET-POET polymer is of a molecular weight in the range of about 15,000 to

50,000, the polyoxyethylene of the POET is of a 85 molecular weight in the range of about 1,000 to 10,000,themolarratioofethy!eneterephthalateto POET unitsiswithintherangeof2:1 to6:1,andthePA polymer is sodium polyacrylate of a molecular weight in the range of about 1,000 to 5,000. 90

5. AcompositionasclaimedinClaim4inwhich the PET-POET polymer is of a molecular weight in the range of 19,000 to 43,000, the polyoxyethylene thereof is of a molecular weight in the range of 2,500 to 5,000 and the PA polymer is sodium polyacrylate of 95 a molecular weight in the range of 1,000 to 3,000.

6. Acomposition as claimed in any one of Claims 1 to 5 in which the detergent is a nonionic detergent which is a condensation product of 3 to 30 ethylene oxide groups per mole of higherfatty alcohol, which

100 higherfatty alcohol is of 10 to 20 carbon atoms.

7. A composition as claimed in any oneof Claims 1 to 6 in which the builder is selected from the group consisting of zeolites and water soluble alkaline polyphosphates, carbonates, bicarbonates, silicates,

105 nitrilotriacetates, borates, citrates, gluconates and mixtures thereof.

8. A detergent composition as claimed in any one of Claims 1 to 7 comprising 10 to 30% of a nonionic detergent which is the condensation product of a

110 higherfatty alcohol of 12 to 15 carbon atoms and 6 to 12 moles of ethylene oxide, 30 to 75% of a builder or a mixture of builders, 2 to 10% of PET-POET polymer of molecular weight in the 19,000 to 25,000 range, 0.3 to 3% of sodium polyacrylate and 4to 14% of moisture. 115

9. A composition as claimed in Claim 8 in which the proportions of such components are 15 to 25% of nonionic detergent, 50 to 70% of builder, 2 to 6% of PET-POET polymer, 0.5to 2% of polyacrylate and 5 to 11% of moisture. 120

10. AcompositionasclaimedinClaim8orClaim 9 in which the builder is sodium tripolyphosphate.

11. Acomposition asclaimed in Claim 10, comprising 50 to 70% of pentasodium tripolyphosphate.

12. Acomposition as claimed in Claim 11 com-125 prising about20% of nonionic detergent, 60% of pentasodium tripolyphosphate, 4% of PET-POET polymer, 1% of sodium polyacrylate and 10% of moisture.

13. A composition as claimed in Claim 8 or Claim 130 9 in which the builder is a mixture of sodium

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carbonate, sodium bicarbonate and Zeolite A.

14. Acomposition asclaimed in Claim ^comprising 10 to 30%, 10 to 25% and15to40%, respectively of the builder components thereof.

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15. Acomposition asclaimed in Claim 14com-prising about 20% of nonionic detergent, 26% of zeolite, 18% of sodium carbonate, 16% of sodium bicarbonate, 4% of PET-POET polymer, 1 % of sodium polyacrylate and 8% of moisture.

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16. AdetergentcompositionasclaimedinClaim 1 substantially as specifically described herein with reference to the accompanying examples.

17. A method of washing laundry and imparting soil release promoting properties to it which compris-

15 es washing such laundry in wash water containing a washing and soil release proportion of a composition as claimed in any one of Claims 1 to 16.

18. A method as claimed in Claim 17inwhichthe laundry is subjected to repeated washings with the

20 composition after intermediate soilingsthereof.

Printed in the United Kingdom for Her Majesty's Stationery Office, 8818935, 7/86 18996. Published at the Patent Office, 25 Southampton Buildings, London WC2A 1AY, from which copies may be obtained.